feat: add LDK debug action to export pathfinding scores

Mirrors the existing network-graph export pattern: a new "Export Scorer"
button under a PATHFINDING SCORER section in LDK Debug calls
node.exportPathfindingScores(), writes the bytes to cacheDir/exports,
and triggers the Android share sheet via FileProvider so the file can
be moved off-device for inspection (e.g. with the scorer-inspect CLI
in synonymdev/ldk-node).

Also nulls the regtest ldkScorerUrl. The regtest endpoint serves a
5-byte minimal payload, so the only effect of pointing the node at it
is a no-op merge; setting it to null makes "we don't use the scorer on
regtest" explicit.

Author: ovitrif

app/src/main/java/to/bitkit/env/Env.kt

@@ -76,7 +76,6 @@ internal object Env {
     val ldkScorerUrl
         get() = when (network) {
             Network.BITCOIN -> "https://api.blocktank.to/scorer-prod"
-            Network.REGTEST -> "https://api.stag0.blocktank.to/scorer"
             else -> null
         }
 

app/src/main/java/to/bitkit/repositories/LightningRepo.kt

@@ -1360,6 +1360,11 @@ class LightningRepo @Inject constructor(
         executeWhenNodeRunning("exportNetworkGraphToFile") {
             lightningService.exportNetworkGraphToFile(outputDir)
         }
+
+    suspend fun exportPathfindingScoresToFile(outputDir: String): Result<File> =
+        executeWhenNodeRunning("exportPathfindingScoresToFile") {
+            lightningService.exportPathfindingScoresToFile(outputDir)
+        }
     // endregion
 
     // region probing

app/src/main/java/to/bitkit/services/LightningService.kt

@@ -1050,6 +1050,14 @@ class LightningService @Inject constructor(
         return loggerLdk.exportNetworkGraphToFile(node, outputDir, fileName)
     }
 
+    suspend fun exportPathfindingScoresToFile(
+        outputDir: String,
+        fileName: String = "pathfinding_scores.bin",
+    ): Result<File> {
+        val node = this.node ?: return Result.failure(ServiceError.NodeNotSetup())
+        return loggerLdk.exportPathfindingScoresToFile(node, outputDir, fileName)
+    }
+
     // endregion
 }
 

app/src/main/java/to/bitkit/ui/screens/settings/LdkDebugScreen.kt

@@ -57,6 +57,7 @@ fun LdkDebugScreen(
         onPasteAndAddPeer = viewModel::pasteAndAddPeer,
         onLogNetworkGraphInfo = viewModel::logNetworkGraphInfo,
         onExportNetworkGraph = viewModel::exportNetworkGraph,
+        onExportScorer = viewModel::exportScorer,
         onRestartNode = viewModel::restartNode,
     )
 }
@@ -70,6 +71,7 @@ private fun LdkDebugContent(
     onPasteAndAddPeer: () -> Unit,
     onLogNetworkGraphInfo: () -> Unit,
     onExportNetworkGraph: (onFileReady: (File) -> Unit) -> Unit,
+    onExportScorer: (onFileReady: (File) -> Unit) -> Unit,
     onRestartNode: () -> Unit,
 ) {
     val context = LocalContext.current
@@ -143,6 +145,20 @@ private fun LdkDebugContent(
                 },
             )
 
+            SectionHeader("PATHFINDING SCORER")
+            SettingsTextButtonRow(
+                title = "Export Scorer",
+                iconRes = R.drawable.ic_share,
+                iconSize = 24.dp,
+                enabled = !uiState.isLoading,
+                onClick = {
+                    onExportScorer { file ->
+                        val uri = FileProvider.getUriForFile(context, Env.FILE_PROVIDER_AUTHORITY, file)
+                        context.shareFile(uri, "application/octet-stream")
+                    }
+                },
+            )
+
             SectionHeader("NODE")
             SettingsTextButtonRow(
                 title = "Restart",
@@ -171,6 +187,7 @@ private fun Preview() {
             onPasteAndAddPeer = {},
             onLogNetworkGraphInfo = {},
             onExportNetworkGraph = {},
+            onExportScorer = {},
             onRestartNode = {},
         )
     }

app/src/main/java/to/bitkit/utils/LoggerLdk.kt

@@ -191,6 +191,25 @@ class LoggerLdk @Inject constructor(
             Logger.error("Failed to export network graph to file", it, context = TAG)
         }
     }
+
+    suspend fun exportPathfindingScoresToFile(
+        node: Node,
+        outputDir: String,
+        fileName: String = "pathfinding_scores.bin",
+    ): Result<File> = withContext(ioDispatcher) {
+        runCatching {
+            val bytes = node.exportPathfindingScores()
+            val outputFile = File(outputDir, fileName)
+            outputFile.writeBytes(bytes)
+            Logger.info(
+                "Exported pathfinding scores '${bytes.size}' bytes to '${outputFile.absolutePath}'",
+                context = TAG,
+            )
+            outputFile
+        }.onFailure {
+            Logger.error("Failed to export pathfinding scores to file", it, context = TAG)
+        }
+    }
 }
 
 class LdkLogWriter(

app/src/main/java/to/bitkit/viewmodels/LdkDebugViewModel.kt

@@ -155,6 +155,32 @@ class LdkDebugViewModel @Inject constructor(
         }
     }
 
+    fun exportScorer(onFileReady: (File) -> Unit) {
+        viewModelScope.launch(bgDispatcher) {
+            _uiState.update { it.copy(isLoading = true) }
+            val outputDir = File(context.cacheDir, DIR_EXPORTS).apply { mkdirs() }.absolutePath
+            lightningRepo.exportPathfindingScoresToFile(outputDir).onSuccess { file ->
+                Logger.info(
+                    "Pathfinding scores exported to '${file.absolutePath}' (${file.length()} bytes)",
+                    context = TAG,
+                )
+                ToastEventBus.send(
+                    type = Toast.ToastType.INFO,
+                    title = "Scorer exported (${file.length()} bytes)",
+                )
+                onFileReady(file)
+            }.onFailure { e ->
+                Logger.error("Failed to export pathfinding scores", e, context = TAG)
+                ToastEventBus.send(
+                    type = Toast.ToastType.ERROR,
+                    title = "Failed to export scorer",
+                    description = e.message,
+                )
+            }
+            _uiState.update { it.copy(isLoading = false) }
+        }
+    }
+
     fun restartNode() {
         viewModelScope.launch(bgDispatcher) {
             _uiState.update { it.copy(isLoading = true) }